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Food security interventions and policies need reliable estimates of crop production and the scope to enhance production on existing cropland. Here we assess the performance of two widely used ‘top-down’ gridded frameworks (Global Agro-ecological Zones and Agricultural Model Intercomparison and Improvement Project) versus an alternative ‘bottom-up’ approach (Global Yield Gap Atlas). The Global Yield Gap Atlas estimates extra production potential locally for a number of sites representing major breadbaskets and then upscales the results to larger spatial scales. We find that estimates from top-down frameworks are alarmingly unlikely, with estimated potential production being lower than current farm production at some locations. The consequences of using these coarse estimates to predict food security are illustrated by an example for sub-Saharan Africa, where using different approaches would lead to different prognoses about future cereal self-sufficiency. Our study shows that foresight about food security and associated agriculture research priority setting based on yield potential and yield gaps derived from top-down approaches are subject to a high degree of uncertainty and would benefit from incorporating estimates from bottom-up approaches. Effective prioritizing of R&D investments in agriculture needs robust estimation of yield gaps for major cropping systems. Yield potential derived from the ‘top-down’ spatial frameworks is subject to a high degree of uncertainty and would benefit from incorporating estimates from ‘bottom-up’ spatial frameworks.

Climate change poses significant risks to food security globally with predictions of 10-20 % decline in rain-fed crop yields by 2050. Sub-Saharan Africa remains highly susceptible to food shortage since over 95 % of the region’s total cropland is rain-fed. Kenya’s over reliance on rain-fed agriculture predisposes the country to climate-induced food insecurity. Murang’a County in Kenya is experiencing climate change challenges manifested in prolonged droughts and floods. The consequences,are failed cropping seasons, soil erosion, landslides, altered crop suitability and a resurgence of human, livestock, crop pests,and diseases,culminating into food insecurity. This study was conducted with Kimandi-Wanyaga community in the Gatanga Sub-County in Murang’a County, Kenya. Residents are smallholder subsistence rain-fed farmers. The study explored the potential of up-scaling crop diversification under the Plantation Establishment and Livelihood Improvement Scheme (PELIS) for food security vis-à-vis climate change. The community’s climate change coping strategies were explored to account for the need to up-scale crop diversification under PELIS. A mixed methods research design was applied whereby a systematic sampling method was used to select 281 household-heads. Three key informants were purposively selected and primary data were collected through a household survey, in-depth key stakeholder interviews, focus group discussions and on-farm trials. Quantitative data were analysed using descriptive and inferential statistics while qualitative data were analysed using thematic and content analysis. The study established that 92.9 % of the community perceived climate change and its impacts. They had adopted a combination of coping strategies most of which,were found to be informed by short-term survival and hence,considered inadequate for long-term adaptation. The PELIS approach had been piloted in Murang’a County and was found to be a promising strategy for crop diversification and food security among forest-adjacent communities. However, only 11 % of the studied community participated in the scheme. Therefore, the study endeavoured to work with the community to promote cultivation of traditional vegetables under PELIS for crop diversification and food security in the face of climate change.The PELIS beneficiaries who adopted cultivation of Black nightshade, Amaranths and Cowpeas managed to produce enough for household consumption and sale of surplus for income. The PELIS,therefore, possesses the co-benefits of climate change adaptation through crop diversification for food security and climate change mitigation through afforestation for carbon sequestration.

Crop phenology represents an integrative indicator of climate change and plays a vital role in terrestrial carbon dynamics and sustainable agricultural development. However, spatiotemporal variations of crop phenology remain unclear at large scales. This knowledge gap has hindered our ability to realistically quantify the biogeochemical dynamics in agroecosystems, predict future climate, and make informed decisions for climate change mitigation and adaptation. In this study, we improved an EVI-curve-based approach and used it to detect spatiotemporal patterns in cropping intensity and five major phenological stages over North America during 2000–2016 using vegetation index in combination with agricultural survey data and other ancillary maps. Our predicted crop phenological stages showed strong linear relationships with the survey-based datasets, with R2, RMSEs, and MAEs in the ranges of 0.35 –0.99, three to ten days, and two to eight days, respectively. During the study period, the planting dates were advanced by 0.60 days/year (p

Drainage of peatlands causes severe environmental damage, including high greenhouse gas emissions. Peatland rewetting substantially lowers these emissions. After rewetting, paludiculture (i.e. agriculture and forestry on wet peatlands) is a promising land use option. In Northeast Germany (291,361 ha of peatland) a multi-stakeholder discussion process about the implementation of paludiculture took place in 2016/2017. Currently, 57% of the peatland area is used for agriculture (7% as arable land, 50% as permanent grassland), causing greenhouse gas emissions of 4.5 Mt CO2eq a−1. By rewetting and implementing paludiculture, up to 3 Mt CO2eq a−1from peat soils could be avoided. To safeguard interests of both nature conservation and agriculture, the different types of paludiculture were grouped into ‘cropping paludiculture’ and ‘permanent grassland paludiculture’. Based on land legislation and plans, a paludiculture land classification was developed. On 52% (85,468 ha) of the agriculturally used peatlands any type of paludiculture may be implemented. On 30% (49,929 ha), both cropping and permanent grassland paludiculture types are possible depending on administrative check. On 17% (28,827 ha), nature conservation restrictions allow only permanent grassland paludiculture. We recommend using this planning approach in all regions with high greenhouse gas emissions from drained peatlands to avoid land use conflicts.

Cropping is responsible for substantial emissions of greenhouse gasses (GHGs) worldwide through the use of fertilizers and through expansion of agricultural land and associated carbon losses. Especially in sub-Saharan Africa (SSA), GHG emissions from these processes might increase steeply in coming decades, due to tripling demand for food until 2050 to match the steep population growth. This study assesses the impact of achieving cereal self-sufficiency by the year 2050 for 10 SSA countries on GHG emissions related to different scenarios of increasing cereal production, ranging from intensifying production to agricultural area expansion. We also assessed different nutrient management variants in the intensification. Our analysis revealed that irrespective of intensification or extensification, GHG emissions of the 10 countries jointly are at least 50% higher in 2050 than in 2015. Intensification will come, depending on the nutrient use efficiency achieved, with large increases in nutrient inputs and associated GHG emissions. However, matching food demand through conversion of forest and grasslands to cereal area likely results in much higher GHG emissions. Moreover, many countries lack enough suitable land for cereal expansion to match food demand. In addition, we analysed the uncertainty in our GHG estimates and found that it is caused primarily by uncertainty in the IPCC Tier 1 coefficient for direct N2O emissions, and by the agronomic nitrogen use efficiency (N-AE). In conclusion, intensification scenarios are clearly superior to expansion scenarios in terms of climate change mitigation, but only if current N-AE is increased to levels commonly achieved in, for example, the United States, and which have been demonstrated to be feasible in some locations in SSA. As such, intensifying cereal production with good agronomy and nutrient management is essential to moderate inevitable increases in GHG emissions. Sustainably increasing crop production in SSA is therefore a daunting challenge in the coming decades.

Climate change threatens humanity yet the provision of food that supports humanity is a major source of greenhouse gases, which exacerbates that threatening process. Developing strategies to reduce the emissions associated with key global commodities is essential to mitigate the impacts of climate change. To date, however, there have been no studies that have estimated the potential to reduce GHG emissions associated with the production of wheat, a key global commodity, at a national scale through changes to wheat production systems. Here, we assess the consequences for net GHG emissions of Australian wheat production from applying three changes to wheat production systems: increasing the rates of fertiliser N to achieve the water-limited yield potential; increasing the frequency of lime applications on acid soils; and changing a two year cropping rotation (from wheat-wheat to legume-wheat). We predict that applying these three changes across the key wheat growing regions in Australia would increase production of wheat and legumes by 17.8 and 5.3 Mt, respectively, over the two-year period. Intensifying Australian production would reduce the need to produce wheat and legumes elsewhere in the world. This would free up agricultural land at the global scale and avoid the need to convert forestland and grassland to cropping lands to meet increasing global demands for wheat. We find that applying these changes across wheat growing zones would reduce the GHGs associated with Australian wheat production by 18.4 Mt CO2-e over the two-year period. Our research supports the notion that intensification of existing agricultural production can provide climate change mitigation. The impacts of intensification on other environmental indicators also need to be considered by policy makers.

Producing the food required to feed the growing global population will inevitably put pressure on the environment and requires sustainable management of agroecosystems. The management strategies should be context-specific, and will require consideration of different stakeholders’ interests, and of the local soil and climatic conditions. We developed a framework to analyse nitrogen (N) management options with the objective of increasing crop production while reducing CO2 and nitrous oxide (N2O) emissions from soil, and applied this framework to Australian rainfed wheat systems using a systems modelling approach. The results indicated that modified N management strategies in Australian rainfed wheat systems could increase average grain yield by up to 76% (from 1.7 to 3.0 Mg ha−1) while substantially reducing net soil and N2O emissions (expressed in CO2 equivalents, CO2-eq), compared with current farming practice. Meta-modelling of the simulation results from 613 sites across the Australian wheat-growing regions indicated that site-specific best N management aimed at increasing yield and reducing net soil CO2-eq emissions significantly correlated with water availability, temperature, and antecedent soil carbon content. The results emphasise the opportunity for well-managed intensification to simultaneously increase yield and reduce soil CO2 and N2O emissions in Australian rainfed cropping regions. The ‘win-win’ N management recommendations should, and can be specified according to local climate and soil conditions.

Global high-resolution crop-specific estimates of greenhouse gas emissions intensity (in 2000) reveal that certain cropping practices contribute disproportionately to emissions, making them suitable targets for climate mitigation policies. Stabilizing greenhouse gas (GHG) emissions from croplands as agricultural demand grows is a critical component of climate change mitigation1,2,3. Emissions intensity metrics—including carbon dioxide equivalent emissions per kilocalorie produced (‘production intensity’)—can highlight regions, management practices, and crops as potential foci for mitigation4,5,6,7. Yet the spatial and crop-wise distribution of emissions intensity has been uncertain. Here, we develop global crop-specific circa 2000 estimates of GHG emissions and GHG intensity in high spatial detail, reporting the effects of rice paddy management, peatland draining, and nitrogen (N) fertilizer on CH4, CO2 and N2O emissions. Global mean production intensity is 0.16 Mg CO2e M kcal−1, yet certain cropping practices contribute disproportionately to emissions. Peatland drainage (3.7 Mg CO2e M kcal−1)—concentrated in Europe and Indonesia—accounts for 32% of these cropland emissions despite peatlands producing just 1.1% of total crop kilocalories. Methane emissions from rice (0.58 Mg CO2e M kcal-1), a crucial food staple supplying 15% of total crop kilocalories, contribute 48% of cropland emissions, with outsized production intensity in Vietnam. In contrast, N2O emissions from N fertilizer application (0.033 Mg CO2e M kcal−1) generate only 20% of cropland emissions. We find that current total GHG emissions are largely unrelated to production intensity across crops and countries. Climate mitigation policies should therefore be directed to locations where crops have both high emissions and high intensities.

Biochar may become a key instrument at the nexus of managed carbon flows, including value added potential in soil amelioration, climate protection, energy supply and organic waste management. This article reflects the potential use of biochar in agriculture from the perspective of the farming economy. Biochar soil amendment in crop production is regarded as a win–win situation, both for assumed increases in cropping yields and carbon sequestration in soil organic matter. However, an extensive review on biochar effect on crop yield has not yet been able to provide compelling arguments to foster more widespread biochar use in cropping systems. Furthermore, the half-lives of biochars are frequently shorter than commonly suggested, and other financial incentives, such as including biochar in carbon credit systems, are not in place to compensate for the extra cost of applying biochar. As a result, we conclude with a somewhat skeptical view for a widespread use of biochar in agriculture in the near future.

The UK, like the rest of the world, is confronting the impacts of climate change. Further changes are expected and they will have a profound effect on agriculture. Future crop production will take place against increasing CO2 levels and temperatures, decreasing water availability, and increasing frequency of extreme weather events. This review contributes to research on agricultural practices for climate change, but with a more regional perspective. The present study explores climate change impacts on UK agriculture, particularly food crop production, and how to mitigate and build resilience to climate change by adopting and/or changing soil management practices, including fertilisation and tillage systems, new crop adoption and variety choice. Some mitigation can be adopted in the shorter term, such as changes in crop type and reduction in fertiliser use, but in other cases the options will need greater investment and longer adaptation period. This is the case for new crop variety development and deployment, and possible changes to soil cultivations. Uncertainty of future weather conditions, particularly extreme weather, also affect decision-making for adoption of practices by farmers to ensure more stable and sustainable production. Even when there is real potential for climate change mitigation, it can sometimes be more difficult to accomplish with certainty on-farm. Better future climate projections and long-term investments will be required to create more resilient agricultural systems in the UK in the face of climate change challenges. © 2016 Society of Chemical Industry.

A recent study in Carbon Management, by Bach et al., argues that biochar amendments’ positive impacts on crop yields and soil carbon sequestration have been overestimated, and biochar amendment to soil is hence unlikely to be an economically viable technique for cropping system management or C abatement. We question the data selection and analysis techniques that the authors used to assess the effect of biochar on crop yield, biochar stability in soil, and biochar production cost. Although the research article was not intended as a meta-analysis – and hence the data reported need not be analyzed with the full rigor of a systematic review – we assert that the employed data set, while containing a sufficient quantity of data, requires closer inspection and a more careful interpretation to avoid significant bias in the conclusions. Furthermore, we assert that proper implementation of biochar and inclusion of non-yield benefits in the analysis would render it more economically viable for both cropping...

Background The environmental costs of fossil fuel consumption are globally recognized, opening many pathways for the development of regional portfolio solutions for sustainable replacement fuel and energy options. The purpose of this study was to create a baseline carbon (C) budget of a conventionally managed sugarcane (Saccharum officinarum) production system on Maui, Hawaii, and compare it to three different future energy cropping scenarios: (1) conventional sugarcane with a 50% deficit irrigation (sugarcane 50%), (2) ratoon harvested napiergrass (Pennisetum purpureum Schumach.) with 100% irrigation (napier 100%), and (3) ratoon harvested napiergrass with a 50% deficit irrigation (napier 50%). Results The differences among cropping scenarios for the fossil fuel-based emissions associated with agricultural inputs and field operations were small compared to the differences associated with pre-harvest burn emissions and soil C stock under ratoon harvest and zero-tillage management. Burn emissions were nearly 2000 kg Ceq ha−1 year−1 in the conventional sugarcane; whereas soil C gains were approximately 4500 kg Ceq ha−1 year−1 in the surface layer of the soil profile for napiergrass. Further, gains in deep soil profile C were nearly three times greater than in the surface layer. Therefore, net global warming potential was greatest for conventional sugarcane and least for napier 50% when deep profile soil C was included. Per unit of biomass yield, the most greenhouse gas (GHG) intensive scenario was sugarcane 50% with a GHG Index (GHGI, positive values imply a climate impact, so a more negative value is preferable for climate change mitigation) of 0.11 and the least intensive was napiergrass 50% when a deep soil profile was included (GHGI = − 0.77). Conclusion Future scenarios for energy or fuel production on former sugarcane land across the Pacific Basin or other volcanic islands should concentrate on ratoon-harvested crops that maintain yields under zero-tillage management for long intervals between kill harvest and reduce costs of field operations and agricultural input requirements. For napiergrass on Maui and elsewhere, deficit irrigation maximized climate change mitigation of the system and reduced water use should be part of planning a sustainable, diversified agricultural landscape.

In responding to climate change, the integration of mitigation, adaptation and food security elements is a conceptual puzzle. This is fuelled by a significant fragmentation of international funding sources and domestic implementation processes aiming at a climate-resilient and low-carbon development in the agricultural sector. To overcome those barriers, the article proposes the establishment of a new institutional set-up, namely a domestic gatekeeper. This institutional concept can act as a mediator linking the global finance architecture with the domestic and local levels, particularly small-scale farmers, thereby promoting food security through climate change mitigation and adaptation measures. Main design features of the gatekeeper concept would be: (i) a high level of organizational capacity to be able to manage access to funds and disbursement of resources to a variety of scattered recipients; (ii) high fiduciary standards; (iii) adequate knowledge of national agricultural settings and appropriate m...

The cropping sector in Australia contributes 2.5% of national greenhouse gas emissions, not accounting for the historical loss of soil carbon. The Australian Government is developing policy initiatives targeted at farmers to encourage changes in management practices that aim to reduce emissions from the agricultural sector. The main policy proposal being developed is a market-based mechanism to pay farmers from an Emissions Reduction Fund using methodologies specified under the Australian Carbon Farming Initiative. The adoption of conservation agriculture practices in the dryland grain sector in Australia shows the potential to achieve emissions reductions in the order of three million tCO2e annually. This paper presents a series of systems models that describe the process of how Australian dryland grain farmers decide to change and adopt conservation agriculture practices. Results indicate that a number of economic and social factors drive the rate of practice change, and change seems to be motivated mostly by the pursuit of productivity benefits rather than environmental benefits. We postulate that it may be more effective for climate policy to directly target the adoption of conservation agriculture practices among Australian dryland grain farmers by promoting the crop productivity benefits likely to be achieved by such practices, rather than attempting to develop a market-based mechanism for carbon payments. Under this approach, emissions reduction outcomes and carbon payments would not be the primary driver for changing farming practices, but rather a concurrent benefit.

During the past decade, the application of agricultural production systems modelling has rapidly expanded while there has been less emphasis on model improvement. Cropping systems modelling has become agricultural modelling, incorporating new capabilities enabling analyses in the domains of greenhouse gas emissions, soil carbon changes, ecosystem services, environmental performance, food security, pests and disease losses, livestock and pasture production, and climate change mitigation and adaptation. New science has been added to the models to support this broadening application domain, and new consortia of modellers have been formed that span the multiple disciplines.There has not, however, been a significant and sustained focus on software platforms to increase efficiency in agricultural production systems research in the interaction between the software industry and the agricultural modelling community. This paper describes the changing agricultural modelling landscape since 2002, largely from a software perspective, and makes a case for a focussed effort on the software implementations of the major models. The agricultural modelling community has broadened its scientific focus over the last decade.The software implementations of the leading agricultural models hasn't changed significantly in the last decade.A focussed effort on agricultural modelling software and process is needed.

One of the grand challenges facing humankind is meeting projected demands for agricultural products in a world undergoing global climate change. As demands increase for the reliable and environmentally responsible supply of food and fiber, how management is adapted to meet these demands will determine the sustainability and climate change mitigation potential of row-crop production systems. This chapter addresses direct greenhouse gas (GHG) emissions from agricultural soils resulting from row-crop production practices. The chapter is focused on globally dominant grain cropping systems (maize, wheat, rice) and on identifying agronomic management practices that help reduce GHG emissions, increase SOC sequestration, and subsequently improve soil health.

Quantifying the carbon footprint (CF) for crop production can help identify key options to mitigate greenhouse gas (GHG) emissions in agriculture. In the present study, both household and aggregated farm scales were surveyed to obtain the data of rice production and farming management practices in a typical rice cultivation area of Northern Jiangxi, China. The CFs of the different rice systems including early rice, late rice, and single rice under household and aggregated farm scale were calculated. In general, early rice had the lower CF in terms of land use and grain production being 4.54 ± 0.44 t CO2-eq./ha and 0.62 ± 0.1 t CO2-eq./t grain than single rice (6.84 ± 0.79 t CO2-eq./ha and 0.80 ± 0.13 t CO2-eq./t grain) and late rice (8.72 ± 0.54 t CO2-eq./ha and 1.1 ± 0.17 t CO2-eq./t grain). The emissions from nitrogen fertilizer use accounted for 33 % of the total CF on average and the direct CH4 emissions for 57 %. The results indicated that the CF of double rice cropping under aggregated farm being 0.86 ± 0.11 t CO2-eq./t grain was lower by 25 % than that being 1.14 ± 0.25 t CO2-eq./t grain under household farm, mainly due to high nitrogen use efficiency and low methane emissions. Therefore, developing the aggregated farm scale with efficient use of agro-chemicals and farming operation for greater profitability could offer a strategy for reducing GHG emissions in China’s agriculture.

Ignoring plant diseases misinforms the climate change and food security debate. Diseases are expected not only to cause more severe crop loss in many areas in the world and threaten food security, but also to decrease the climate change mitigation capacity of forests, of other natural ecosystems and of producing crops. However, if research, policy and industry join forces to obtain the multidisciplinary knowledge necessary to adapt integrated pest management (IPM) to the changing climate, it is expected that sufficiently resilient cropping systems can be developed in time. This was the main conclusion of the International Conference on Climate Change and Plant Disease Management held in Evora, Portugal, in November 2010.

The purpose of this paper is to summarize the challenges and the practical successes that a selected number of countries are experiencing in moving towards 'climate-smart' agriculture while also meeting the food requirements of a growing population, broader economic development and green growth objectives. It complements papers prepared in 2010 on technologies and policy instruments, research, and farmers' perspectives. The paper is also intended to provide a broad country perspective to two additional papers produced for a meeting of African Ministers of Agriculture which took place in Johannesburg in September 2011. The main conclusion is that a number of countries have made impressive progress in integrating 'climate-smart agriculture' into broader development and growth programs. Several countries are supporting policy measures and programs to conserve soil and moisture while enhancing productivity and competitiveness, and are addressing the particular concerns of drought-prone semi-arid areas. They are improving agricultural water management and watershed management, and addressing sea-surges, salinity and coastal flooding. Some countries are also including climate-smart agriculture as a core element in broader green growth agendas. The private sector has a key role to play in climate-smart agriculture, especially where the enabling environment has been favorable. Achieving climate-smart agriculture needs an integrated approach, tackling productivity and food security, risk and resilience, and low carbon growth together, but integration and institutional coordination remains a challenge in many countries.

The climate change (CC) caused by increase in atmospheric concentration of CO2 and other Greenhouse Gases (GHGs), can be addressed through adaptation and mitigation strategies. Adaptation consists of strategies which minimize vulnerability to CC. The objective is to increase resilience of the ecosystems and communities through adoption of specific sustainable land management (SLM) techniques that have adaptive benefits. On the other hand, the goal of mitigation strategies is to enhance soil and vegetation (land) sinks for absorbing atmospheric CO2 and to minimize net emissions. In the context of the resource-poor and small landholders of the developing countries, adaptation to CC is essential. Adaptation strategies are needed to enhance the positive and reduce the negative effects of CC. Adaptation is also needed because complete mitigation of CC may never occur. The strategy is to adopt those SLM technologies which have both adaptation and mitigation impacts at multiple scales (household, community, and watershed, national, global). There are four major areas in the tropics and sub-tropics where adoption of SLM technologies can help to both adapt to and mitigate CC: (i) tropical forest ecosystems (TFEs), (ii) tropical savannah and rangeland ecosystems (TSREs), (iii) world cropland soils, and (iv) salinized and degraded/desertified lands. Nonetheless, adoption of SLM technologies in the temperate regions (North America, Europe, Australia, Japan) is also important to adapting to CC. However, this report focuses on SLM options for developing countries of the tropics and sub-tropics.